The present invention generally refers to the realisation, and to the execution modalities for operation and maintenance of overhead lines for telecommunications, comprising a cable sustained by posts, and more particularly it relates to movable anchoring or xe2x80x9cmooringxe2x80x9d devices which permit the realisation of the overhead line and the performance of maintenance works without the intervention of technicians at a certain height above the ground.
The wide diffusion of the network formed by cables sustained by posts and the realisation modality of these plants, are critical with regard to operation and maintenance, in view of the costs involved, the service quality, and the safety conditions during the execution of the work.
These critical aspects are essentially due to the requirement of the access of technicians at a certain height above the ground, and to different orographic and environmental characteristics of the territory where the posts are installed.
In fact, besides the stability conditions of the plants themselves, the actual environmental and orographic features of the territory will determine both the possibility of access to a position located a certain height above the ground level, and the way this is to be done: use of a controlled platform, a ladder, crampons (climbing irons).
Naturally, a comparison between the means employed and the time required for the work, on the one hand, and the quality of the intervention and the safety of the personnel, on the other hand, leads to different results, for each modality of access at a certain height above ground level, but in all cases they do not lead to optimum results.
An object of the present invention is to provide a method of realisation of overhead line plants for telecommunications via cable, which radically limits the number of necessary interventions to be performed by the appointed technicians, at a certain height above the ground level.
A further object of the present invention is to provide a method allowing the maintenance and the replacement of cables to be performed directly from the ground, thereby eliminating the need for access at a certain height above ground level.
Still another object of the present invention is to provide a method of realisation and maintenance of overhead line plants for telecommunications, said plants crossing road paths, and wherein the method allows the maintenance and the replacement of cables to be performed directly from the ground, without the need of lowering the overhead line to the road level and stopping vehicle traffic.
A last object of the present invention is to provide a method of realisation and maintenance of overhead line plants for telecommunications, which employs standard components, materials and technologies in the field of fixed line telephone plants, so that the proposed devices used to carry out the method, will have limited costs and their use is facilitated.
These and other objects which will be clarified in the description, are obtained by means of a method according to which the mooring or anchor device of the self-gripping two-way supports which sustain the cables, is made integral to a movable structurexe2x80x94and not to fixed points relative to the post by the use of known threaded pinsxe2x80x94, wherein the movable structure is free to slide along the sustaining post and comprises a chain allowing to lower the overhead line to the countryside ground level, and its subsequent lifting at the end of the maintenance intervention. The lowering of the line to the ground level may be obtained by exploiting the action of the gravity force.